Conference virke::mrmemo

187.0. "MRMEMO stopped working in DDS load ?" by SUOSWS::MOOG (ute_moog at suo) Fri Sep 24 1993 20:30

    Hello,
    
    I have a problem at my preferred customer site with MRMEMO and DDS.
    Problem:
    We load MEMO user addressing data from MEMO into DDS with a tool called
    DDS SYNC (not the EMS service). This tool simply uses command files and
    MBMAN to apply its changes, add users or delete users.
    
    During the last few load runs we experienced dramatic failures.
    MEMOs were only handled with 1 per 3-5 minutes, MR messages did not
    come through as MEMO always had priority. In the end we had about 3000
    mails in the mailbox on the Message Router .
    The load run included about 4000 changes and some ADDS and DELs in DDS.
    The DDS database contains about 30000 subscribers and 3 WSNs.
    
    The ALL-IN-1 users on the cluster (6*6000) experienced no problems in 
    reading DDS entries, MR/X and DEC Mailworks showed no exceptional behavior.
    Only MRMEMO stopped working which led to terrible problems at the customer.
    
    What we have seen from file access is, that MRMEMO is the only
    application that accesses DDS$INQUE.DAT ? As this file was about 50000
    blocks in size at that stage , I assume that MRMEMO looks through the
    INQUE and the other database files. The assembling phase for MEMO to MR
    messages takes exremely long. Is the assumption about the search
    algorithm correct or can you describe
    what exactly is done when looking for information in DDS (address
    validation and DDS validation for MR to MEMO sender are enabled) ?
    
    Is there anything (process parameters or else) that you can think of,
    thhat may enhance performance of the MEMO server ?
    
    A 2nd problem that reoccurred to me in those circumstances were the
    Read Receipts that are sent from A1 back to MEMo for every message ?
    There was a patch for that ?
    
    Thanks for reading this lengthy note...
    
    Ciao
    Ute 
    

    
    Hi Ute,
    
    We simply use the (unofficial) DDS API to access DDS, just as ALL-IN-1,
    MRX et al. We certainly don't access the DDS queue files directly, but
    The API puts the requests from MRMEMO into the In queue.
    
    There are some options in the API as to how to perform the search
    MRMEMO uses the options (LOCAL/WORLD/ESCALATE). It is possible that the
    difference in processing time between MRMEMO and the other applications
    has something to do with the setting of these options.
    
>    Is there anything (process parameters or else) that you can think of,
>    thhat may enhance performance of the MEMO server ?
    
    Not really, I think it has to do with DDS being choked, not MRMEMO.
    
>    A 2nd problem that reoccurred to me in those circumstances were the
>    Read Receipts that are sent from A1 back to MEMo for every message ?
>    There was a patch for that ?
    
    Not a patch but an undocumented MRMEMO switch:
    
    MRMMAN> DEFINE/REQUEST=NORECEIPT
    
    
    cheers,
    
    	Stefan
    

Thanks,

I will try the switch.

Things are back to normal and we will do some things to keep things running 
better, like more MR$NBS directories a second MEMO server and daily 
housekeeping.

I hope this helps.

I am still very curious, why the INQUE is handled by that API. What calls 
does MR/X or DEC Mailworks use then ? They do not access the queue files.


Thanks Ute